Owning a car involves handling auto maintenance tasks promptly. While you are likely familiar with changing the oil and rotating the wheels, you may not know when to replace the spark plugs in your engine. These components provide the initial spark to ignite the fuel and allow the engine to run. If you're unsure when to replace the spark plugs, below are several common indicators.

When Should You Swap a Car's Spark Plugs?

1. Excessive Visual Wear

Spark plugs usually last about 80,000 miles, and if your vehicle is nearing this amount, you should inspect the plugs. If you have a used car and are unsure when the last change occurred, check them when you do another routine auto maintenance task, such as changing the oil. New spark plugs are bright white, while older, worn plugs are discolored and may even be black or brown. This is due to the heat and debris in the engine wearing them out.

2. Rough Idling 

When you start the car or stop at a light, pay attention to how the vehicle sounds. If you hear rattling or knocking, the spark plugs could be getting old. Rough idling can also make the car feel like it is shaking, rumbling, or vibrating more than usual. When you handle auto maintenance tasks promptly, the engine will sound like a steady hum and won't cause excessive vibrations. Even if you have a loud, powerful engine, the sound and feeling should be steady. If it produces intermittent or stuttering noises, replace the spark plugs.

3. Misfiring

If the spark plugs are not reliable, they cannot properly ignite the fuel in the engine, which results in a misfire. This is a sudden reverberation that you can feel throughout the cabin. It sounds like a loud pop and you may feel the car slowing down. The vehicle may also have trouble accelerating. Once this happens, check the plugs; if they're in good condition, make an auto maintenance appointment to determine the exact cause.

If you need help replacing the spark plugs in your car, contact Brogan & Folz Firestone in Cincinnati, OH. For more than 50 years, their team has been helping drivers with a variety of auto maintenance tasks, including tire rotations, oil changes, and check engine light repairs. They can even handle full engine rebuilds. Visit them online for more information about their services. Call (513) 574-3040 to schedule an appointment.